[MossyRocks]

Have you tried any of the light pollution filters? They might allow you to get great shots without traveling so far.

My opinion on light pollution filters is that they offer a big benefit to those just starting out but as your skills in editing evolve and improve you will reach a point where not using one is better as you don't get the color shift they introduce which can be hard to remove and by avoiding them you get a few extra useable photons per shot. For the most part I have stopped using them and will only use them when I shoot from my massively light polluted backyard where the orange glow goes to the zenith.

[PhilRich]

Have you tried any of the light pollution filters? They might allow you to get great shots without traveling so far.

Thanks,
barondla

I'm totally unaware of light pollution filters for night pictures, what is a resource for information concerning them?

[barondla]

I'm totally unaware of light pollution filters for night pictures, what is a resource for information concerning them?

Astrophotography Archives - Farpoint Astro

Haven't looked at this new site in detail, hopefully it has info.
Thanks,
barondla

[poidabro]

My opinion on light pollution filters is that they offer a big benefit to those just starting out but as your skills in editing evolve and improve you will reach a point where not using one is better as you don't get the color shift they introduce which can be hard to remove and by avoiding them you get a few extra useable photons per shot. For the most part I have stopped using them and will only use them when I shoot from my massively light polluted backyard where the orange glow goes to the zenith.

hmmmmm maybe I can/should save 4 hours a night travel time and shoot from suburbia, at least until my skills improve to warrant the travel to my friend's farm.... what is the size city you live in? my city (Newcastle, Australia ) has about half a million people, but is on the coast.

[poidabro]

Have you tried any of the light pollution filters? They might allow you to get great shots without traveling so far.

Thanks,
barondla

thank you for the advice ! even though where I will try viewing in suburbia is far from ideal (with only a sliver of sky visible amongst other negatives ) it does cut out 3-4hrs travel, so due to advice in this thread I'm thinking of getting this filter for my k1 "Astronomik CLS Clip-Filter Pentax K-1"

---------- Post added 08-22-20 at 07:11 PM ----------

ok so I'm fairly certain that 645z is not the all around camera for me due to weight on the telescope, image circle size on the telescope, and lens speed for wide angle star photos. I'm gonna stick with the k1. I really appreciate everyone's input and efforts with that input. I'm also gonna try getting a light pollution filter for my telescope imaging and save some transport time by using the telescope in suburbia, whilst getting valuable practice on imaging and processing before travelling to the countryside

[DeadJohn]

...I'm gonna stick with the k1...

On most threads, we're talking about spending other members' money. This thread is a rare case of saving other members' money

[MossyRocks]

hmmmmm maybe I can/should save 4 hours a night travel time and shoot from suburbia, at least until my skills improve to warrant the travel to my friend's farm.... what is the size city you live in? my city (Newcastle, Australia ) has about half a million people, but is on the coast.

I live in a suburb out side Minneapolis and St. Paul in Minnesota. However my city really likes lights and uses the worst ones with glass globes that send as much light up as they do out and to the ground. Each lamp post has 2 of these on it and in my neighborhood they are every 4 or houses. In the down town area they are every 50 feet on both sides of every road. In the town next to me they have a huge refinery. If you are familiar with the Bortle scale my backyard is a bortle 8 and about a mile away it is a 9. I went and looked up where you are at and you are in a much better area than I am as it looks like the bright areas of newcastle are a Bortle 6 or 7 with 4 and 5 not too far away. You can get a good idea of the bortle class of an area using this site by clicking on a spot.

For me I have a 45 minute drive to get to a bortle 5 area and it gets to over 2 hours to get darker than that but things really start getting dark at a 2 hour drive.

[barondla]

I live in a suburb out side Minneapolis and St. Paul in Minnesota. However my city really likes lights and uses the worst ones with glass globes that send as much light up as they do out and to the ground. Each lamp post has 2 of these on it and in my neighborhood they are every 4 or houses. In the down town area they are every 50 feet on both sides of every road. In the town next to me they have a huge refinery. If you are familiar with the Bortle scale my backyard is a bortle 8 and about a mile away it is a 9. I went and looked up where you are at and you are in a much better area than I am as it looks like the bright areas of newcastle are a Bortle 6 or 7 with 4 and 5 not too far away. You can get a good idea of the bortle class of an area using this site by clicking on a spot.

For me I have a 45 minute drive to get to a bortle 5 area and it gets to over 2 hours to get darker than that but things really start getting dark at a 2 hour drive.

Thanks for the website. I live in a Bortle 5 area. Driving 5 miles gets me to a Bortle 4. The trade off is I'm no longer on my property.

I have access to a 7" refractor with 2.7" focuser. It should handle the 645Z image circle. Where would I get the proper camera attachment? Might try some astrophotography when work settles down.

Thanks,
barondla

[MossyRocks]

Where would I get the proper camera attachment? Might try some astrophotography when work settles down.

That I don't know. Usually the goal is getting to M42 or T-mount with telescopes as from going from either of those to a modern camera is easy but 645 would be harder as it isn't a common mount. Getting to M42 to T is actually pretty easy with most scopes. There are places that will build a custom mount adapter but they aren't cheap and with the 645 you might have problems with register distance. Drop over into the astrophotography group as I'm sure someone over there has some better knowledge on what is available for going from telescope to camera and could point you in the right direction. I am over there but still play in the shallow end with a small equatorial, astrotracer, and a giant slab of 400mm f/2.8 glass.

[whwang]

Loos like you decide to stay with K1. I think this is a wise decision given what you have.

645z is a wonderful camera. It is one of my best investment in astrophotography over perhaps 30 years. However, as others have pointed out, you need a scope with large image circle to do justice to 645z. Not many scopes can do that, and definitely not a GSO. (A heavily retrofitted GSO can, perhaps.) Indeed, even with an FF camera, the GSO may have issues. You will need a good field flattener or large focal reducer on a GSO RC to produce a flat field for an FF camera, and this would required a focuser much better than what GSO offers in its standard package.

For astrophotography without a telescope, 645z is not a perfect choice either. The camera is really excellent in terms of sensor performance, but lenses from Pentax are just not good for astrophotography. (I try to be polite here. So I just say they are "not good.") First of all, the apertures are too small to start with, as you probably had also realized. Then, almost all of them have terrible coma/astigmatism in the corners and require severe stopping down of the aperture. To take really decent pictures, you will need to go to a dark place and integrate for hours to overcome the small aperture+stopping down. I see that you have an equatorial mount. So in principle, you can do that. But that's really not the best thing to do. You will be torturing yourself. Use an FF camera plus a good large-aperture lens (like those from Sigma) and you will be in a much better position to take stunning photos, and this will cost much less.

If you do have a telescope that can cover 645z's sensor well, I would say go for it. You won't regret. For everything else (astrophoto-wise), don't.

You are welcome to check my gallery. There are many 645z astrophotos.

---------- Post added 08-23-20 at 11:43 PM ----------

Thanks for the website. I live in a Bortle 5 area. Driving 5 miles gets me to a Bortle 4. The trade off is I'm no longer on my property.

I have access to a 7" refractor with 2.7" focuser. It should handle the 645Z image circle. Where would I get the proper camera attachment? Might try some astrophotography when work settles down.

Thanks,
barondla

There is at least one off-the-shelf 645z adapter:
M65x1 female thread to Pentax 645 camera mount adapter

All you need now is an adapter with M65x1 thread and whatever attachment required by your 2.7" focuser.

Note that you will also need a field flattener for your refractor. A 7" refractor with a 2.7" focuser should be able to fully illuminate the sensor of 645z, but the stars won't be good in the corners as the focal surface is usually curved. Once you have a flattener, you need to pay attention to its back focus.

[poidabro]

Loos like you decide to stay with K1. I think this is a wise decision given what you have.

645z is a wonderful camera. It is one of my best investment in astrophotography over perhaps 30 years. However, as others have pointed out, you need a scope with large image circle to do justice to 645z. Not many scopes can do that, and definitely not a GSO. (A heavily retrofitted GSO can, perhaps.) Indeed, even with an FF camera, the GSO may have issues. You will need a good field flattener or large focal reducer on a GSO RC to produce a flat field for an FF camera, and this would required a focuser much better than what GSO offers in its standard package.

For astrophotography without a telescope, 645z is not a perfect choice either. The camera is really excellent in terms of sensor performance, but lenses from Pentax are just not good for astrophotography. (I try to be polite here. So I just say they are "not good.") First of all, the apertures are too small to start with, as you probably had also realized. Then, almost all of them have terrible coma/astigmatism in the corners and require severe stopping down of the aperture. To take really decent pictures, you will need to go to a dark place and integrate for hours to overcome the small aperture+stopping down. I see that you have an equatorial mount. So in principle, you can do that. But that's really not the best thing to do. You will be torturing yourself. Use an FF camera plus a good large-aperture lens (like those from Sigma) and you will be in a much better position to take stunning photos, and this will cost much less.

If you do have a telescope that can cover 645z's sensor well, I would say go for it. You won't regret. For everything else (astrophoto-wise), don't.

You are welcome to check my gallery. There are many 645z astrophotos.

---------- Post added 08-23-20 at 11:43 PM ----------



There is at least one off-the-shelf 645z adapter:
M65x1 female thread to Pentax 645 camera mount adapter

All you need now is an adapter with M65x1 thread and whatever attachment required by your 2.7" focuser.

Note that you will also need a field flattener for your refractor. A 7" refractor with a 2.7" focuser should be able to fully illuminate the sensor of 645z, but the stars won't be good in the corners as the focal surface is usually curved. Once you have a flattener, you need to pay attention to its back focus.

great advice. thank you. it would have sucked to have spent $13000aud on a camera and lens only to find it doesn't suit my fave interests!

---------- Post added 08-24-20 at 01:34 AM ----------

Loos like you decide to stay with K1. I think this is a wise decision given what you have.

645z is a wonderful camera. It is one of my best investment in astrophotography over perhaps 30 years. However, as others have pointed out, you need a scope with large image circle to do justice to 645z. Not many scopes can do that, and definitely not a GSO. (A heavily retrofitted GSO can, perhaps.) Indeed, even with an FF camera, the GSO may have issues. You will need a good field flattener or large focal reducer on a GSO RC to produce a flat field for an FF camera, and this would required a focuser much better than what GSO offers in its standard package.

For astrophotography without a telescope, 645z is not a perfect choice either. The camera is really excellent in terms of sensor performance, but lenses from Pentax are just not good for astrophotography. (I try to be polite here. So I just say they are "not good.") First of all, the apertures are too small to start with, as you probably had also realized. Then, almost all of them have terrible coma/astigmatism in the corners and require severe stopping down of the aperture. To take really decent pictures, you will need to go to a dark place and integrate for hours to overcome the small aperture+stopping down. I see that you have an equatorial mount. So in principle, you can do that. But that's really not the best thing to do. You will be torturing yourself. Use an FF camera plus a good large-aperture lens (like those from Sigma) and you will be in a much better position to take stunning photos, and this will cost much less.

If you do have a telescope that can cover 645z's sensor well, I would say go for it. You won't regret. For everything else (astrophoto-wise), don't.

You are welcome to check my gallery. There are many 645z astrophotos.

---------- Post added 08-23-20 at 11:43 PM ----------



There is at least one off-the-shelf 645z adapter:
M65x1 female thread to Pentax 645 camera mount adapter

All you need now is an adapter with M65x1 thread and whatever attachment required by your 2.7" focuser.

Note that you will also need a field flattener for your refractor. A 7" refractor with a 2.7" focuser should be able to fully illuminate the sensor of 645z, but the stars won't be good in the corners as the focal surface is usually curved. Once you have a flattener, you need to pay attention to its back focus.

btw how do I find your photos? I'm a bit of a noob in forums...

[whwang]

btw how do I find your photos? I'm a bit of a noob in forums...

I put two links to my gallery in my signature (below the post).

[TDvN57]

Thanks for the website. I live in a Bortle 5 area. Driving 5 miles gets me to a Bortle 4. The trade off is I'm no longer on my property.

I have access to a 7" refractor with 2.7" focuser. It should handle the 645Z image circle. Where would I get the proper camera attachment? Might try some astrophotography when work settles down.

Thanks,
barondla

RafCamera recently made me a mount for the 645. On their website they also have a lot of adapters. The owner is Rafael and is very helpful. I think the website is at rafcamera.com

[DeadJohn]

Thanks for the website. I live in a Bortle 5 area. Driving 5 miles gets me to a Bortle 4. The trade off is I'm no longer on my property.

I have access to a 7" refractor with 2.7" focuser. It should handle the 645Z image circle. Where would I get the proper camera attachment? Might try some astrophotography when work settles down.

Thanks,
barondla

Who is the focuser manufacturer? Is the focuser already threaded? Check their website for adapters.

If you pick another brand of adapter due to availability or price, make sure your focuser is true 2.7". I think Astrophysics uses 2.7" threads while Zeiss uses 68mm, very close sizes but not identical.

You might need to combine 2 adapters: 645 to a generic wide thread or to 6x7, then a 2nd adapter from that generic thread to your focuser specs.

Some resources for large format adapters. None of these links are likely to be exactly what you need but will get you started.
5030 – Pentax 645 Adapter – Hutech E-store
PreciseParts Build-An-Adapter
Baader M84 to M68 Adapter - PENTAX
6x7 Outer Bayonet for AP 2.7" Thread - attaches 67RT--, A3512, ADA671, ADA672, 67RLEOS, 67RLNIK, A1260, A1261 and A1262 to AP 2.7" Thread including 27TVPH (ADA2767) - Astro-Physics

[barondla]

Loos like you decide to stay with K1. I think this is a wise decision given what you have.

645z is a wonderful camera. It is one of my best investment in astrophotography over perhaps 30 years. However, as others have pointed out, you need a scope with large image circle to do justice to 645z. Not many scopes can do that, and definitely not a GSO. (A heavily retrofitted GSO can, perhaps.) Indeed, even with an FF camera, the GSO may have issues. You will need a good field flattener or large focal reducer on a GSO RC to produce a flat field for an FF camera, and this would required a focuser much better than what GSO offers in its standard package.

For astrophotography without a telescope, 645z is not a perfect choice either. The camera is really excellent in terms of sensor performance, but lenses from Pentax are just not good for astrophotography. (I try to be polite here. So I just say they are "not good.") First of all, the apertures are too small to start with, as you probably had also realized. Then, almost all of them have terrible coma/astigmatism in the corners and require severe stopping down of the aperture. To take really decent pictures, you will need to go to a dark place and integrate for hours to overcome the small aperture+stopping down. I see that you have an equatorial mount. So in principle, you can do that. But that's really not the best thing to do. You will be torturing yourself. Use an FF camera plus a good large-aperture lens (like those from Sigma) and you will be in a much better position to take stunning photos, and this will cost much less.

If you do have a telescope that can cover 645z's sensor well, I would say go for it. You won't regret. For everything else (astrophoto-wise), don't.

You are welcome to check my gallery. There are many 645z astrophotos.

---------- Post added 08-23-20 at 11:43 PM ----------



There is at least one off-the-shelf 645z adapter:
M65x1 female thread to Pentax 645 camera mount adapter

All you need now is an adapter with M65x1 thread and whatever attachment required by your 2.7" focuser.

Note that you will also need a field flattener for your refractor. A 7" refractor with a 2.7" focuser should be able to fully illuminate the sensor of 645z, but the stars won't be good in the corners as the focal surface is usually curved. Once you have a flattener, you need to pay attention to its back focus.

Thank you for the information. I'll order the adapter and research field flattners. May try the scope, 1st without flattner, to see if I can even do astrophotography.

Your photos are inspirational. The image quality is fabulous. I enjoyed viewing them and highly recommend others follow your links.

Thanks for sharing,
barondla